I wouldn't risk it.
I am pretty sure that the Aussie made Sterns are toughened glass, only because I have seen a Cosmic Princess shatter into a million glass cubes when hit on the edge on concrete.
I think that maybe the older Gottlieb's are ordinary glass but I am not sure.
Toughened glass can take a fair bit of pressure on the face but hit it the wrong way on the edge and its game over.